How and when to suspect spontaneous coronary artery dissection: novel insights from a single-centre series on prevalence and angiographic appearance.

ABSTRACT

AIMS: Spontaneous coronary artery dissection (SCAD) is an underdiagnosed entity of acute coronary syndrome (ACS). Its prevalence remains unclear due to a challenging diagnosis, particularly in instances of intramural haematoma without intimal rupture. In the present study, we aimed to 1) estimate the prevalence of SCAD among acute coronary syndrome (ACS) patients managed in a French coronary care centre, 2) demonstrate the value of specific angiographic signs for diagnosing SCAD, and 3) confirm the incremental value of intracoronary imaging in ambiguous cases. METHODS AND RESULTS: From 1999 to 2014, 55 cases of SCAD (all women, mean age 50.1 years) were diagnosed. Ignoring age, 51 (92.7%) had ≤2 cardiovascular risk factors. Thirty-six were diagnosed prospectively during the latter period (2012-2014). Among these, SCAD accounted for 35.7% of ACS (20/56) in women <60 years with ≤1 cardiovascular risk factor. Upon close investigation, five angiographic features commonly observed with SCAD were identified 1) absence of atheroma on other coronary arteries, 2) radiolucent flap(s), 3) contrast dye staining of the arterial wall, 4) starting and/or ending of the angiographic ambiguity on a side branch, 5) long narrowing of lumen calibre smooth and linear, or stenosis of varying severity mimicking a "stick insect" or "radish" aspect. Three of the above five signs were present in 51 (92.7%) cases. Optical computed tomography (OCT) was performed in 19 cases with no complication. All explored arteries had evidence of intramural haematoma and/or intimomedial membrane separation. An intimal rupture was observed in 10 (52.6%) patients. The diseased segment initiated or ended on a side branch in 14 (73.7%) patients. CONCLUSIONS: SCAD accounts for approximately one third of ACS in young women with ≤1 CRF. The combination of specific angiographic signs and OCT imaging facilitates the diagnosis of ambiguous cases without intimal rupture.